Because of its length and width Chile is a country of contrasts. On a sunny day, the peak of the Aconcagua mount, located in Argentina, can be seen from the coast of Valparaiso. At the same time, the country is so long that covers 38 degrees Latitude, from a little further north the Tropic of Capricorn to the Antarctic Polar Circle. On the other hand, the driest desert in the world is located in Chile (Atacama, 23-26° S) as well as one of the areas with the largest water availability (Aysen, 44-47° S).

Considering the diversity in weather, physiographic traits and lithologic characteristics existing in Chile, it is possible to identify along the country five great subareas which posses weather characteristics and similar hydrology responses: a) Arid North (18-27° South Latitude), with scarce precipitation; b) Central North (27-33° S), or area of transverse valleys, with an average precipitation of 100 mm and an agricultural activity focused on the early production of fruit for export and foreign markets; c) Central Area of Chile (33-38° S), characterized by three morphologic longitudinal belts, and where the major population and agricultural production of the country are brought together, with precipitation up to 1500 mm/year on the South border, and a vegetable, annual and fruit crops oriented agricultural activity; d) South Area (38-42° S), with precipitation over 1500 mm/year, mainly focused on stockbreeding; e) Far South (from 42° S), with precipitation that may reach 4000 mm/year. This evident climatic and hydrological polarity North/South is also reflected in terms of the water resources availability for the population, where there is also an important change in the country. In the Central North and North areas this does not exceed, except for the Coquimbo Region, the 1000 m3/hab/year. Extreme cases are those of the North Area, where this figure ranges between 250 and 700. By contrast, on the Central Area this indicator reaches the figure of 3000 m3/hab/year, and in the South Area of the country it exceeds the 4000 m3/hab/year (Salazar, 2003).

Regarding the water use in Chile, it exceeds 2.300 m3/s, 30% corresponding to consumption uses (mainly agriculture, as discussed below) and 70% to non consumption uses (mainly hydroelectrical use). From the consumption uses, between 15 to 20% corresponds to industrial, mining and tap water uses, while between 80 to 85% of the water is set aside for irrigation on agricultural activities, allowing the development of this activity in a little more than a million hectares. However, water is frequently used with as high as 30% rate efficiency (distribution, conduction and application). On the other hand, the water distribution for the various uses is highly variable along the country. In fact, while in the northern regions of the country water is used mainly in the mining industry, in the North-Central, Central and South parts of the country the use of water is mainly for agricultural irrigation purposes.

Figure 1: Chile and the five mentioned sub-areas, main cities and political division.

The aim of this chapter is to render a general view of the authors about the needs and opportunities for research existing in Chile, related to water management on the agricultural activity. For this purpose, given the Chilean context, we will consider aspects such as the current national vision to become an agricultural food power, the current legal frame, and others factors conditioning the management of the water resources on the Chilean agriculture. After describing the context, some needs for research for the management of the water resources will be discussed.

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